Smallpox mixes make a stir.
D035843:Biomedical Research; D002487:Centers for Disease Control and Prevention, U.S.; D002678:Chimera; D015925:Cryopreservation; D006801:Humans; D012900:Smallpox Vaccine / Q000008:administration & dosage*; D014481:United States; D012901:Variola virus / Q000235:genetics / Q000472:pathogenicity; D014944:World Health Organization
D012900:Smallpox Vaccine